Plecotus auritus

Geographic Range

Plecotus auritus is found all across Eurasia, from Spain east to Japan, and south into India.

• Biogeographic Regions
• palearctic palearctic
  • native native

Habitat

In general, P. auritus seem to prefer higher altitudes. In the summer, the long-eared bat can most often be found roosting in hollow trees at the edge of parks or woodlands. They are also commonly found clustering next to a chimney or along the beams of large roof spaces in stables, barns, lofts, and older buildings. From mid October to early April they hibernate in caves, mineshafts, hollow trees, under roofs, and in underground sites. Favorite roost sites of the long-eared bat can often be indicated by stains on the timbers.

• Habitat Regions
• temperate temperate
• terrestrial terrestrial

• Terrestrial Biomes
• forest forest

• Other Habitat Features
• suburban suburban

Physical Description

As their common name implies, P. auritus have large ears--almost as long as their bodies. When in flight, the bats hold the ears fully erect and extended forward. At rest, their ears fold and curl sideways in a way that resembles ram horns. During hibernation the bats fold and tuck ears down, so that only the long pointed ear cover is visible.

P. auritus have relatively large eyes without a tapetum lucidum, and slit-shaped nostrils that open laterally. They usually weigh 6-12 grams and females are slightly larger than males. They have long, silky fur that is brownish on the upper side and grayish brown below. The dental formula for the P.auritus is 2/3, 1/1, 2/3, 3/3=36.

(Grzimek, 1975; Howard, 1995; Swift, 1998)

• Other Physical Features
• endothermic endothermic
• bilateral symmetry bilateral symmetry

Reproduction

• Mating System
• polygynandrous (promiscuous) polygynandrous (promiscuous)

These bats and mate in autumn. For males, sperm production reaches its peak in late August and September, when the testes are descended. The testes regress and sperm production ceases in November. Females delay fertilization until spring (late April or May).

Females only bear one offspring per breeding season (every year); twins are very rare.

• Key Reproductive Features
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• viviparous viviparous
• delayed implantation delayed implantation

The gestation period of Long-eared bats is relatively long, but the specifics are unknown. The young are altricial at birth, born pink and hairless with disproportionately large feet, used to grasp their mothers' fur once they are born. They feed on their mothers' milk until they are three weeks old, and then are left in the roost while the mother leaves to forage for food. At six weeks old they are weaned and able to forage for themselves. Females are often ready to breed at one year old and males are sexually mature at fifteen months.

(Roberts and Hutson, 2001; Swift, 1998)

• Parental Investment
• altricial altricial
• female parental care female parental care

Lifespan/Longevity

Climate is a very important factor for the survival of the young long-eared bat. Poor weather during lactation results in delayed growth, abandonment by mother and high mortality. Although records show that P. auritus are able to live up to thirty years, the average lifespan is seven years for males, sixteen years for females, and fifteen years for the sexes combined. High longevity could be due to the large amounts of time spent in a state of torpor, when the metabolic rate is very low.

Behavior

P. auritus group together in relatively small groups (no more than 80 individuals). The only social relationship that has been identified is the mother/offspring relationship. Females remain in natal roosts their entire lives and males are likely to depart to another roost.

Long-eared bats emerge from roost after sunset and do not return again until shortly before sunrise. They hover in the confined roost briefly before emerging, displaying their ability to remain stationary in the air without any forward motion. There is no convincing evidence of migration of P. auritus , but they do hibernate from autumn to March.

(Grzimek, 1975; Swift, 1998)

• Key Behaviors
• nocturnal nocturnal
• motile motile
• solitary solitary
• colonial colonial

Communication and Perception

• Perception Channels
• tactile tactile
• chemical chemical

Food Habits

P. auritus are insectivorous, feeding mainly on Lepidoptera (moths). They are opportunistic foragers, feeding on the most available insects, including beetles, flies, earwigs, and spiders. Long-eared bats forage in a variety of ways, such as catching insects in free flight, landing on the ground to capture prey, or hovering in mid-air to listen for movements of insects to pick them off the foliage. They forage at night, usually relatively close to their roost.

(Burton, 1962; Roberts and Hutson, 2001)

• Primary Diet
• carnivore carnivore
  • insectivore insectivore

• Animal Foods
• insects
• terrestrial non-insect arthropods

Predation

Long-eared bats avoid most predators by only flying at night; however, they are still sometimes captured by some nocturnal predators such as owls and cats. The domestic cat is the most significant mammalian predator, especially to bats roosting under the roofs of houses. Their habit of flying close to the ground to forage and landing to catch insects makes them especially vulnerable to cats.

Ecosystem Roles

P. auritus harbor relatively few parasites comparted to other bats, perhaps due to its small colony size. Several species of fleas in the family Ischnopsyllidae and mites in Spinturnicidae have been recorded on long-eared bats.

The only species of internal parasites that have been noted in P. auritus are bacteria in the genus Grahamella .

Economic Importance for Humans: Positive

They consume large numbers of insect pests.

• Positive Impacts
• controls pest population

Conservation Status

Additional Links

Encyclopedia of Life

Contributors

Leah Thompson (author), University of Michigan-Ann Arbor, Kate Teeter (editor), University of Michigan-Ann Arbor.

References

Burton, M. 1962. University Dictionary of Mammals of the World . NY: Thomas Y. Crowell Company.

Grzimek, 1975. Animal Life Encyclopedia . NY: Van Nostrand Reinhold Company.

Howard, R. 1995. York, England: William Sessions Limited.

Roberts, G., A. Hutson. 2004. "The Bat Conservation Trust" (On-line). Accessed 03/23/04 at http://www.bats.org.uk/batinfo/ble.htm .

Swift, S. 1998. Long-eared Bats . London: T&AD Poyser Ltd..